The present invention generally relates to a hand grip, and more particularly relates to a hand grip contoured according to the muscle structure of the palm, and employed as in insert between the hand and the shank of the instrument to be gripped.
It is a well known practice to provide hand grips on various handles to obtain a comfortable feel as well as to reduce or eliminate the torsional movement between the handle and the hand of the user. Hand grips such as the type used on power tools or bicycle handle bars are contoured according to the finger surfaces to aid the user or rider in maintaining a firm grip on the handle.
U.S. Pat. No. De. 208,516 discloses a crutch handle grip design of solid structure used as an integral part of the crutch. The disadvantage of this approach is that each tool, or piece of sporting equipment to which the principal is applicable must be made with such a grip, and is thereby useful to only those persons with matching hand shapes and sizes.
U.S. patent application Ser. No. 354,198 filed Mar. 3, 1982 and assigned to the assignor of the present application is for a racing bicycle handle bar grip which generally conforms to the palm musculature to relieve median nerve pressure when the rider supports his upper body weight on the handle bars during extended riding excursions or races. These grips have an increased palmar surface area for distribution of such weight thereon and are not well suited for wrapping the fingers and the thumb around the combined grip and handle bar. Also, to prevent the grip disclosed in this application from rotating on the handle bar, the recessed curved area for receiving the tubular handle bar is angled so as to fit the curved part of the handle bar.
There is thus a need for a power grip insert for use with tools such as hammers, and sporting equipment such as golf clubs and tennis rackets which permit a user to clinch his fist around both the tool or the racket together with the power grip to optimize the gripping power between the hand and the handle shaft.
The fingers and thumb of a human hand, being jointed for movement, are well adapted for gripping objects. However, the palmar arch, the thenar and hypothenar musculature are not contoured to optimally conform to a tubular-like instrument shank. The need for a power grip fittable into a fist clenched around the shank of an instrument is even more evident in view that the flexing of the hand and finger muscles around the shank, in an effort to hold it firmly, only exacerbates muscle stress by reducing the conformance of the hand flesh to the tool. This serves only to increase muscle fatigue and strain on the median nerve located in the palmar area.
It is therefore a primary object of the present invention to provide a personal power grip insert with one surface particularly contoured according to the palm of the user's hand, and another surface for receiving the handle or shank of the instrument to be held.
It is another object of the invention to provide a power grip insert sized to conveniently fit into a fist clenched around the instrument shank, and fill the space between the shank and the dissimilar palmar contour of the user's hand.
Another object of the invention is to provide a power grip which particularly conforms to a user's hand, and which can be used on various tools and equipment with similar-sized handle shanks.
Still another object of the invention is to provide a power grip device adapted for permanent fastening to the instrument handle itself, to a glove or temporarily to the user's hand with a surgical-type adhesive.
It is yet another object of the invention to provide a power grip device which permits the shank of the instrument to be rotated by loosening the grip of the clenched fist, such as is necessary in changing from a forehand to a backhand grip on a tennis racket.
A further object of the present invention is to provide a grip insert with surface areas contoured according to the palm musculature with such muscles in the relaxed state.
Other objects and advantages of the invention will become apparent from the following detailed description when considered in connection with the attached drawings.